ralle
Hello,
I have the following problem. I need to produce a series of enlargements measuring 9x9cm. Unfortunately, my ‘DUNCO MODELL II-66’ enlarger, when used with an ‘El Nikkor 2.8/50’, cannot do this. I can only focus from 12x12cm upwards. At that size, the distance from the lens to the paper is large enough.
I have now fitted an 80mm lens. This would give me the desired size of 9x9cm. Could I avoid vignetting by using a small aperture, e.g. f/16?
Thank you for your interest.
Correction:
Correction... here is the correct text ;-)
I have the following problem. A series of enlargements is to be 9x9cm
in size. Unfortunately, my ‘DUNCO MODEL II-66’ enlarger,
when used with an ‘El Nikkor 5.8/80’, cannot do this. I can only
focus from 14x14cm upwards. Then the distance from the lens to the paper is large enough.
So I’ve now fitted a _Rodagon 50mm lens_. That would give
me the desired size of 9x9cm. Could I avoid vignetting by using a small aperture,
e.g. f/16?
Regards, Ralle
Renate
Hello,
You shouldn’t experience any vignetting with the 80 mm lens. It might be visible with the 50 mm lens if the negative is larger than 24 x 36 mm. The 80 mm lenses can generally handle negatives up to 60 x 60 mm. Higher-end models can also enlarge 60 x 70 mm negatives.
Best regards,
Renate
Magirus
Hi Ralle,
Your comment has left me a bit confused.
I’ve just been to Duka – a 6x6 negative can be made sharp to less than 8x8.
Setup: 80mm lens, 6x6 image stage and the lighting unit for medium format.
Was the lighting unit that goes in the top of the head the one designed for 35mm film?
Regards, Ben
heinrich
Hello,
I have the following problem. I need to produce a series of enlargements measuring 9x9cm. Unfortunately, my ‘DUNCO MODEL II-66’ enlarger, when used with an ‘El Nikkor 2.8/50’, cannot do this. I can only focus from 12x12cm upwards. At that size, the distance between the lens and the paper is large enough.
I’ve now fitted an 80mm lens. That would give me the desired size of 9x9cm. Could I avoid vignetting by using a small aperture, e.g. f/16?
Thank you for your interest.
Regards, Ralle
?
?
Hello,
Do you have a condenser illumination? My 80mm lens reliably vignettes at KB if I forget to swap the 50mm condenser for the 80mm condenser. The physicists among us would be better placed to explain why that is.
Regards
Heinrich
ralle
Hello,
There should be no vignetting with the 80 mm lens. It might be visible with the 50 mm lens if the negative is larger than 24 x 36 mm. The 80 mm lenses can generally handle negatives up to 60 x 60 mm. More expensive versions can also enlarge 60 x 70 mm negatives.
I was referring to the 80 mm as well.
€
Regards, Ralle
ralle
Hi Ralle,
Your comment has left me a bit confused.
I’ve just been to Duka – a 6x6 negative can be focused to less than 8x8.
Setup: 80mm lens, 6x6 image stage and the light unit for medium format.
Was the light unit that goes in the top of the head originally fitted for 35mm film?
Regards, Ben
On my ‘DUNCO MODEL II-66’ enlarger, as far as I know there’s no special light unit for MF for the head. Just the image stage and lens. In my case, that’s an El Nikkor 5.8/80
Extension rings for the M39 thread might just solve my problem?!
Regards, Ralle
€
ralle
€
<BLOCKQUOTE class="ipsBlockquote" data-author="ralle" data-cid="18298" data-time="1424852665">
<DIV>
Hello,
I have the following problem. I need to produce a series of enlargements measuring 9x9cm. Unfortunately, my enlarger, the 'DUNCO MODEL II-66', cannot achieve this when used with an 'El Nikkor 2.8/50'. I can only focus from 12x12cm upwards. At that size, the distance from the lens to the paper is large enough.
I have now fitted an 80mm lens. This would give me the desired size of 9x9cm. Could I avoid vignetting by using a small aperture, e.g. f/16?
Thank you for your interest.
Regards, Ralle
€
?
</div>
</blockquote>
Hello,
Do you have a condenser light? My 80mm lens reliably vignettes at KB if I forget to swap the 50mm condenser for the 80mm condenser. The physicists among us would be better placed to explain why that is.
€
Regards
Heinrich
€
</DIV>
</BLOCKQUOTE>
The enlarger houses a halogen lamp.
Regards, Ralle
€
Magirus
Well, the "lighting unit" is a mixing box with a double condenser.
What I'm getting at is the mixing box. The 35 doesn't fully light up the stage.
Kind regards, Ben
ralle
Well, the "lighting unit" is a mixing box with a double condenser.
What I'm getting at is the mixing box. The 35 doesn't fully illuminate the stage.
Best regards, ben
I’m not quite sure what you mean. With my 80mm, MF is well lit. My problem is that, when used with an ‘El Nikkor 5.8/80’, I can’t get 9x9cm enlargements. 14x14cm is the smallest size. I’m surprised that it works for you.
But I was advised to try using extension rings.?
?
Regards, Ralle
Tandemfahren
Hi Ralle,
Extension rings (if you can find suitable ones) are the right approach. Your bellows extension isn’t long enough.
But have a look at how the lens is mounted in the standard on your camera. Many cameras have a tube that can be fitted for short or long extension (just flip it over), or the manufacturer may supply a replacement one.
In my opinion, it won’t work with the 50mm lens; the image circle is too small.
Frank
piu58
> In my opinion, it won’t work with a 50mm lens; the image circle is too small.
?
?
With ‘close-ups’, the image circle becomes larger. This means that a 50mm lens might be able to illuminate a small format during enlargement. After all, that’s the reverse optical path to a close-up. I’d also make myself a round dodging thingamajig, so you can let a bit more light into the corners.
?
Stopping down only improves the illumination moderately; medium apertures are sufficient. But there’s plenty of light here, so you can work at f/16. I don’t see any advantage over f/8, though.
Wolf_XL
...why keep it simple when you can make it complicated... ;-) The Dunco requires a dedicated lens board for extension tubes with a focal length >75mm.
?
See also the appendix, last page, part no. 16
Tandemfahren
Uwe’s right. I’ve just tried it out myself. A 50mm lens is actually enough for me, even at full aperture. Focusing is a bit tricky, though, because the focusing screen doesn’t fit underneath anymore.
@Wolf: see, that’s the sort of thing I meant.
Frank
ralle
...why keep it simple when you can make it complicated... ;-) The Dunco requires a dedicated lens board for extension tubes with a focal length >75mm.
€
See also the attachment, last page, part no. 16
I’ve bought a few different M39 extension rings on eBay. That should do the trick, shouldn’t it?!
Regards, Ralle
ralle
€
<blockquote class="ipsBlockquote" data-author="Wolf_XL" data-cid="18335" data-time="1425227035">
<div>
...why keep it simple when you can make it complicated... ;-) The Dunco requires a dedicated lens board for extension tubes with a focal length >75mm.
€
See also the attachment, last page, part no. 16
I’ve bought a few different M39 extension rings on eBay. That should do the trick, surely?!
Regards, Ralle
€
</div>
</blockquote>
ralle
Hello,
I’ve managed to find a set of extension rings (4 extension rings, M 39, 26–16–8–5 mm) on eBay.
That solves my problem. Thank you for your interest.
Regards, Ralle
